Information processing apparatus, information processing method, and program

ABSTRACT

Provided is an information processing apparatus including a position sensor for detecting position information, and a detection times control unit for acquiring detection accuracy information regarding detection accuracy of the position sensor based on a detection result of the position sensor, and controlling the number of detection times of the position sensor based on the acquired detection accuracy information.

BACKGROUND

The present disclosure relates to an information processing apparatus,an information processing method, and a program.

In recent years, information processing apparatuses such as mobilephones are becoming increasingly multi-functional. Therefore, a user canobtain various pieces of information by using various functionsinstalled in an information processing apparatus. For example, someinformation processing apparatuses are capable of detecting positioninformation of a user by a position sensor, and of presenting thedetected position information.

JP 2011-81431A discloses a mobile terminal, having a position sensor,that is capable of detecting daily actions of a user.

SUMMARY

Now, at the time of detecting a position by a position sensor, morepower is consumed than when performing detection by a motion sensor orthe like. Particularly, power consumption further increases as theoperation time of the position sensor becomes longer.

The present disclosure proposes a method that allows to suppress powerconsumed at the time of performing position detection by a positionsensor.

According to the present disclosure, there is provided an informationprocessing apparatus which includes a position sensor for detectingposition information, and a detection times control unit for acquiringdetection accuracy information regarding detection accuracy of theposition sensor based on a detection result of the position sensor, andcontrolling the number of detection times of the position sensor basedon the acquired detection accuracy information.

Also, according to the present disclosure, there is provided aninformation processing method which includes acquiring, based on adetection result of a position sensor for detecting positioninformation, detection accuracy information regarding detection accuracyof the position sensor, and controlling, based on the acquired detectionaccuracy information, the number of detection times of the positionsensor.

Furthermore, according to the present disclosure, there is provided aprogram for causing a computer to execute acquiring, based on adetection result of a position sensor for detecting positioninformation, detection accuracy information regarding detection accuracyof the position sensor, and controlling, based on the acquired detectionaccuracy information, the number of detection times of the positionsensor.

Furthermore, according to the present disclosure, the number ofdetection times of the position sensor can be reduced in a casedetection accuracy is low, for example, by controlling the number ofdetection times of the position sensor based on the acquired detectionaccuracy information. As a result, power consumption at the time ofperforming position detection by the position sensor can be suppressed.

As described above, according to the present disclosure, power consumedat the time of performing position detection by a position sensor can besuppressed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram showing a configuration of an information processingapparatus according to a first embodiment;

FIG. 2 is a block diagram showing a configuration of an actionrecognition engine of the information processing apparatus according tothe first embodiment;

FIG. 3 is a histogram showing a relationship between accuracy of aposition sensor and the number of acquisition times;

FIG. 4 is a schematic diagram showing a first example of an acquisitiontimes control process;

FIG. 5 is a schematic diagram showing a second example of theacquisition times control process;

FIG. 6 is a schematic diagram showing a third example of the acquisitiontimes control process;

FIG. 7 is a diagram for describing the third example of the acquisitiontimes control process;

FIG. 8 is a schematic diagram for describing an example modification ofthe acquisition times control process;

FIG. 9 is a schematic diagram for describing an example modification ofthe acquisition times control process;

FIG. 10 is a schematic diagram for describing an example modification ofthe acquisition times control process;

FIG. 11 is a flow chart showing an operation of the informationprocessing apparatus at the time of performing the acquisition timescontrol process according to the first embodiment;

FIG. 12 is a schematic diagram for describing an overview of anacquisition times control process with respect to position informationaccording to a second embodiment;

FIG. 13 is a flow chart showing an operation of the informationprocessing apparatus at the time of performing the acquisition timescontrol process according to the second embodiment;

FIG. 14 is a schematic diagram for describing an overview of anacquisition times control process with respect to position informationaccording to a third embodiment;

FIG. 15 is a flow chart showing an operation of the informationprocessing apparatus at the time of performing the acquisition timescontrol process according to the third embodiment;

FIG. 16 is a schematic diagram for describing an overview of anacquisition times control process with respect to position informationaccording to a fourth embodiment;

FIG. 17 is a flow chart showing an operation of the informationprocessing apparatus at the time of performing the acquisition timescontrol process according to the fourth embodiment;

FIG. 18 is a schematic diagram for describing an overview of anacquisition times control process with respect to position informationaccording to a fifth embodiment; and

FIG. 19 is a flow chart showing an operation of the informationprocessing apparatus at the time of performing the acquisition timescontrol process according to the fifth embodiment.

DETAILED DESCRIPTION OF THE EMBODIMENT(S)

Hereinafter, preferred embodiments of the present disclosure will bedescribed in detail with reference to the appended drawings. Note that,in this specification and the appended drawings, structural elementsthat have substantially the same function and configuration are denotedwith the same reference numerals, and repeated explanation of thesestructural elements is omitted.

Additionally, the explanation will be given in the following order.

1. First Embodiment

-   -   1-1. Overview of Information Processing Apparatus    -   1-2. Configuration of Action Recognition Engine    -   1-3. Acquisition Times Control Process for Position Information    -   1-4. Operation of Information Processing Apparatus

2. Second Embodiment

3. Third Embodiment

4. Fourth Embodiment

5. Fifth Embodiment

1. First Embodiment 1-1. Overview of Information Processing Apparatus

An overview of an information processing apparatus 100 according to afirst embodiment of the present disclosure will be described withreference to FIG. 1. FIG. 1 is a diagram showing a configuration of theinformation processing apparatus 100 according to the first embodiment.

The information processing apparatus 100 is a mobile terminal to be usedby a user, such as a mobile phone, a PDA or the like, for example. Theinformation processing apparatus 100 has a function of displaying mapinformation on a screen, and selecting peripheral information or thelike.

As shown in FIG. 1, the information processing apparatus 100 includes aninput unit 110, a display unit 120, a communication unit 130, a positioninformation detection unit 140, a motion sensor 142, a storage unit 150,and a control unit 160.

The input unit 110 has a function of receiving input of operationinformation from a user of the information processing apparatus 100. Theinput unit 110 is configured from an input device such as a switch, abutton, a touch panel, a keyboard, a mouse, or the like.

The display unit 120 has a function of displaying various types ofinformation under the control of the control unit 160. For example, thedisplay unit 120 displays map information. The display unit 120 isconfigured from a display device such as a liquid crystal display, aplasma display, an organic EL display, or the like.

The communication unit 130 is a communication interface having afunction of a transmission unit and a reception unit for performingcommunication with an external appliance under the control of thecontrol unit 160. The communication unit 130 is configured from acommunication device such as a wired or wireless LAN, a Bluetoothcommunication card, a communication router, a communication modem, orthe like.

The position information detection unit 140 is a global positioningsystem (GPS) receiver, for example, and detects position information(information on latitude, longitude and the like) of the informationprocessing apparatus 100 by performing wireless communication with anexternal appliance. For example, the GPS receiver receives dataindicating orbit information, time information and the like from aplurality of GPS satellites, and detects the position of the informationprocessing apparatus 100 based on the difference between pieces ofinformation indicated by the data, difference between data arrivaltimes, or the like. Additionally, the position information detectionunit 140 is not limited to be the GPS receiver. For example, theposition information detection unit 140 may detect the position of theinformation processing apparatus 100 by receiving radio frequencyidentification (RFID) or information from a Wi-Fi access point.Furthermore, the position information detection unit 140 may detect theposition of the information processing apparatus 100 by receiving, forexample, data indicating information regarding a cell in whose servicearea the information processing apparatus 100 is present, from a basestation device of a mobile phone network of the information processingapparatus 100 (a mobile phone).

The motion sensor 142 detects information regarding movement or state ofthe information processing apparatus 100. As the motion sensor 142, a3-axis accelerometer (an accelerometer, a gravity sensor, a falldetection sensor, or the like) or a 3-axis gyro sensor (an angularvelocity sensor, a hand-blur correction sensor, a geomagnetic sensor, orthe like) is used, for example.

The storage unit 150 has a function of storing various types ofinformation to be used by the control unit 160. For example, the storageunit 150 stores position information acquired by the positioninformation detection unit 140, action information acquired by themotion sensor 142, and the like. The storage unit 150 is configured froma storage device such as a magnetic storage device, a semiconductorstorage device, an optical storage device, or the like.

The control unit 160 has a function of controlling the overall operationof the information processing apparatus 100. For example, the controlunit 160 can control operation of the information processing apparatus100 based on operation information output from the input unit 110,position information acquired by the position information detection unit140, action information acquired by the motion sensor 142, or the like.The control unit 160 is configured from a CPU, a ROM, and a RAM.

1-2. Configuration of Action Recognition Engine

A configuration of an action recognition engine 200 of the informationprocessing apparatus 100 according to the first embodiment will bedescribed with reference to FIG. 2. FIG. 2 is a block diagram showing aconfiguration of the action recognition engine 200 of the informationprocessing apparatus 100 according to the first embodiment.

As shown in FIG. 2, the action recognition engine 200 includes aposition data acquisition unit 210, a motion data acquisition unit 220,an action recognition processing unit 230, which is an example of anaction recognition unit, and an acquisition times control unit 240,which is an example of a detection times control unit. Additionally,these functional units are realized by the control unit 160 shown inFIG. 1.

The position data acquisition unit 210 acquires position data of theinformation processing apparatus 100 (user). The position dataacquisition unit 210 acquires the position data of the informationprocessing apparatus 100 based on position information detected by theposition information detection unit 140. For example, the position dataacquisition unit 210 acquires current position information of theinformation processing apparatus 100 (user). The position dataacquisition unit 210 outputs the position data acquired to the actionrecognition processing unit 230 and the acquisition times control unit240.

The motion data acquisition unit 220 acquires motion data regardingmovement or state of the information processing apparatus 100. Themotion data acquisition unit 220 acquires the motion data regardingmovement or state of the information processing apparatus 100 based oninformation detected by the motion sensor 142. The motion dataacquisition unit 220 outputs the motion data acquired to the actionrecognition processing unit 230.

The action recognition processing unit 230 recognizes an action of auser carrying the information processing apparatus 100. The actionrecognition processing unit 230 recognizes the action of the user of theinformation processing apparatus 100 based on position data input fromthe position data acquisition unit 210 and motion data input from themotion data acquisition unit 220, and acquires action information of theuser.

The acquisition times control unit 240 acquires detection accuracyinformation regarding detection accuracy of the position informationdetection unit 140 based on a detection result of the positioninformation detection unit 140 (a position sensor), and controls thenumber of acquisition times (the number of detection times) of theposition information of the position information detection unit 140based on the detection accuracy information acquired. For example, theacquisition times control unit 240 increases the number of acquisitiontimes by reducing acquisition cycle of the position information, andreduces the number of acquisition times by increasing the acquisitioncycle of the position information. Although details will be describedlater, it thereby becomes possible to suppress power consumed at thetime of performing position detection by the position sensor.

The acquisition times control unit 240 may divide detection accuracywhose degrees cover a predetermined range, and may control the number ofposition detection times for each of the divided degrees. For example,the acquisition times control unit 240 may perform control so as toreduce stepwise the number of position detection times for a region,within the predetermined range, with a high degree of detectionaccuracy. Also, the acquisition times control unit 240 may performcontrol so as to reduce stepwise the number of position detection timesfor a region, within the predetermined range, with a low degree ofdetection accuracy. Furthermore, in the case the predetermined range isdivided into a small region, a medium region, and a large regionaccording to the degree, the acquisition times control unit 240 maycontrol the number of position detection times for the medium region tobe greater than the number of position detection times for the smallregion and the large region. By controlling the number of positiondetection times for each degree of detection accuracy in this manner,optimal number of position detection times according to the situationthe user is in can be set. As a result, power consumed at the time ofposition detection can be suppressed without impairing the function ofposition detection.

1-3. Acquisition Times Control Process for Position Information

FIG. 3 is a histogram showing a relationship between accuracy of theposition sensor and the number of acquisition times. In daily life, auser goes to various places indoors and outdoors. Accordingly, whenlooking at the actions of the user over a short period of time, thedistribution of the histogram is not uniform, as shown in the leftdiagram of FIG. 3.

On the other hand, when looking at the actions of the user over a longperiod of time, the histogram of the accuracy of the position sensor canbe assumed to be uniformly distributed, as shown in the right diagram ofFIG. 3. Here, the center of the histogram indicates the average numberof acquisition times of the position data and the average accuracy. Theacquisition times control unit 240 according to the present embodimentcontrols the number of acquisition times based on the accuracy of theposition sensor so that the center of the histogram shifts to apreferable position.

FIG. 4 is a schematic diagram showing a first example of the acquisitiontimes control process. As shown in FIG. 4, the acquisition times controlunit 240 performs control so as to reduce the number of acquisitiontimes for parts where the accuracy of the histogram is low.Specifically, the acquisition times control unit 240 reduces stepwisethe number of acquisition times as the accuracy falls. That is, theacquisition times control unit 240 reduces stepwise the number ofacquisition times by increasing stepwise the acquisition cycle. As aresult, the center C of the accuracy histogram shifts to the lowerright. The overall number of acquisition times is thereby reduced, and,also, the average accuracy is increased.

By reducing the number of acquisition times at parts where the accuracyis low in this manner, power consumption can be effectively suppressed.Also, influence on position detection is small even if the number ofacquisition times is reduced for where the accuracy is low. Thus,according to the first example, power consumption can be suppressedwithout reducing the accuracy of position detection.

FIG. 5 is a schematic diagram showing a second example of theacquisition times control process. As shown in FIG. 5, the acquisitiontimes control unit 240 performs control so as to reduce the number ofacquisition times for parts where the accuracy of the histogram is high.Specifically, the acquisition times control unit 240 reduces stepwisethe number of acquisition times as the accuracy increases. That is, theacquisition times control unit 240 reduces stepwise the number ofacquisition times by increasing stepwise the acquisition cycle.Additionally, the number of acquisition times is reduced lessdrastically than in the first example. As a result, the center C of theaccuracy histogram shifts to the lower left. The overall number ofacquisition times is thereby reduced.

By reducing the number of acquisition times at parts where the accuracyis high in this manner, power consumption can be effectively suppressed.Also, when the number of acquisition times is reduced for parts wherethe accuracy is high, the average accuracy is reduced, but the influenceon position detection is small. This is because, since the accuracy ofeach piece of data is high at parts where the accuracy is high, theaccuracy which has been averaged is barely changed even when the numberof pieces of data used for averaging is small.

FIG. 6 is a schematic diagram showing a third example of the acquisitiontimes control process. The third example is a process which combines thefirst example and the second example described above. That is, theacquisition times control unit 240 reduces stepwise the number ofacquisition times as the accuracy falls, and, also, reduces stepwise thenumber of acquisition times as the accuracy increases. As a result, thecenter C of the accuracy histogram shifts to the lower right. Powerconsumption can be effectively suppressed while hardly impairing theaccuracy of position detection.

Describing in detail with reference to FIG. 6, the number of acquisitiontimes is reduced stepwise in a first region (a region with low accuracy;corresponds to the small region) and a third region (a region with highaccuracy; corresponds to the large region) on the horizontal axis.Additionally, the number of acquisition times in the third region islarger than the number of acquisition times in the first region. Also,in a second region (corresponding to the medium region) between thefirst region and the third region, the number of acquisition times isconstant and is not reduced. This is because, since the accuracy of thesecond region is lower compared to the accuracy of the third region, itis difficult, in the averaging process of position detection, to reducethe number of acquisition times if the processing accuracy is to beimproved.

FIG. 7 is a diagram showing the third example of the acquisition timescontrol process. For example, if a user is staying at a location wherethe accuracy is low, position information with low accuracy is acquiredat the specific period of the stay. Thus, by performing theabove-described control in advance, the number of acquisition times ofposition information with low accuracy can be reduced, and,consequently, power consumption can be suppressed.

FIG. 8 is a schematic diagram for describing an example modification ofthe acquisition times control process. The acquisition times controlunit 240 may regard the number of acquisition times as a function of theaccuracy, and control the position of the center C of the accuracyhistogram. For example, as shown in FIG. 8, the accuracy histogram maybe approximated by a linear function in such a manner as the followingEquations (1) and (2).y=ax+b  Equation (1)y=cx+d  Equation (2)

Moreover, a, b, c, and d are constant terms.

For example, if the constant terms a to d are decided according to atarget distribution, the center C (p, q) of the accuracy histogram isdecided. Accordingly, by calculating and dynamically evaluating how thecentre C will be positioned when the constant terms a to d are changed,it becomes possible to control the center C. The position of the centerof the accuracy histogram can thereby be controlled with higheraccuracy.

FIG. 9 is a schematic diagram for describing an example modification ofthe acquisition times control process. The acquisition times controlunit 240 may calculate the histogram from the record of the actualposition data, and may perform control so that the center shifts to theoptimal position. Such a process is effective when it is difficult toassume a uniformly distributed histogram. As shown in FIG. 9, theacquisition times control unit 240 controls the center of the histogramby taking into account the relationship of amounts of adjustment a and band the center C′ (p′, q′) after shifting.

FIG. 10 is a schematic diagram for describing an example modification ofthe acquisition times control process. With the control processdescribed above, the position of the center is inclined to go down.Accordingly, as shown in FIG. 10, the acquisition times control unit 240may set a lower limit (a bottom line L) for the center C and performcontrol so that the center C does not fall below the lower limit.Additionally, the lower limit is the number of position detection timesnecessary for the action recognition process, for example.

1-4. Operation of Information Processing Apparatus

An operation of the information processing apparatus 100 at the time ofperforming the acquisition times control process according to the firstembodiment will be described with reference to FIG. 11.

FIG. 11 is a flow chart showing an operation of the informationprocessing apparatus 100 at the time of performing the acquisition timescontrol process according to the first embodiment. This flow chartstarts from the activation of the position information detection unit140, for example.

The acquisition times control process is realized by the CPU of thecontrol unit 160 executing a program stored in the ROM. Additionally,the program to be executed may be stored in a recording medium such as acompact disk (CD), a digital versatile disk (DVD), a memory card or thelike, or may be downloaded from a server or the like via the Internet.

First, the acquisition times control unit 240 generates an accuracyhistogram as shown in FIG. 4 and the like (step S102). Then, theacquisition times control unit 240 calculates the center C of thehistogram (step S104).

Next, the acquisition times control unit 240 determines whether thecalculated center is outside a target range (step S106). In the case thecenter is outside the target range (the target range is set in advance)in step S106 (Yes), the acquisition times control unit 240 calculatesthe amount of adjustment with respect to the number of acquisition times(step S108). For example, the acquisition times control unit 240calculates, as the amount of adjustment, the amount of adjustment of theacquisition cycle.

Next, the acquisition times control unit 240 adjusts the number ofacquisition times according to the amount of adjustment calculated (stepS110). For example, the acquisition times control unit 240 performscontrol so as to reduce the number of acquisition times, as shown inFIGS. 4 to 6 and the like. Additionally, in the case the center iswithin the target range in step S106 (No), the acquisition times controlunit 240 does not adjust the number of acquisition times.

Then, the acquisition times control unit 240 repeats the processesdescribed above (steps S102 to S110) until the present process iscomplete (step S112: No). When the present process is complete (stepS112: Yes), the position information detection unit 140 (a positionsensor) detects position information according to the controlled numberof acquisition times.

According to the first embodiment described above, the number ofdetection times of the position information detection unit 140 can bereduced in a case the detection accuracy is low, for example, bycontrolling number of the detection times of the position informationdetection unit 140 based on the acquired detection accuracy information.As a result, power consumption at the time of performing positiondetection by the position information detection unit 140 can besuppressed.

2. Second Embodiment

An information processing apparatus 100 according to a second embodimentincludes a plurality of position sensors (position information detectionunits 140), and can select and use a plurality of position sensors. Theinformation processing apparatus 100 can maintain the accuracy whilekeeping down the number of acquisition times, by operating a positionsensor while taking into account the characteristics or performance(detection performance) of a plurality of position sensors.

An acquisition times control process with respect to positioninformation according to the second embodiment will be described withreference to FIG. 12. FIG. 12 is a schematic diagram for describing anoverview of an acquisition times control process with respect toposition information according to the second embodiment.

In the following, an explanation will be given assuming that a pluralityof position sensors are a GPS sensor (corresponding to a first positionsensor) and a WiFi sensor (corresponding to a second position sensor).The acquisition times control unit 240 performs scoring and comparisonof the characteristics or performance (detection performance) of the GPSsensor and the WiFi sensor, and selects a sensor suitable for thesituation the user is in and causes the same to operate. For example, asshown in FIG. 12, when the user is in the environment of a situation 1,the acquisition times control unit 240 selects the GPS sensor and causesthe same to operate, and when the user is in the environment of asituation 2, the acquisition times control unit 240 selects the WiFisensor and causes the same to operate.

Here, the characteristics or performance of the GPS sensor or the WiFisensor can be evaluated based on the standpoints of, for example, thepower consumption per unit time of the position sensor, the length of asection of the latest acquired position data, and the average value ofthe accuracy of the latest acquired position data. The GPS sensor andthe WiFi sensor can then be compared to each other by performing scoringwith respect to the three standpoints by the following Equation (3), forexample.S=aX+bY+cZ  Equation (3)

“S” is a device selection score. “a”, “b”, and “c” are coefficients, andthe coefficient a is a negative value, and the coefficients b and c arepositive values, for example. “X” is a value obtained by normalizing thepower consumption per unit time of the sensor, “Y” is a value obtainedby normalizing the length of a section of the latest acquired positiondata, and “Z” is a value obtained by normalizing the average value ofthe accuracy of the latest acquired position data.

The acquisition times control unit 240 then compares the deviceselection score S(gps) of the GPS sensor and the device selection scoreS(wifi) of the WiFi sensor, and selects a sensor with a higher score. Itthereby becomes possible to select, reflecting the characteristics orperformance of the position sensors, the most appropriate positionsensor from a plurality of position sensors and cause the same tooperate.

Now, in the case of alternately, or simultaneously, causing the GPSsensor and the WiFi sensor to operate to calculate the device selectionscores S(gps) and S(wifi), influence on the power consumption is anissue of concern. Thus, the device selection scores S(gps) and S(wifi)may be compiled as a database in advance. For example, the deviceselection scores S(gps) and S(wifi) may be stored in the storage unit150. In similar places or times, the characteristics or performance ofthe GPS sensor and the WiFi sensor tend to have similar values. By usingthis tendency and selecting the GPS sensor or the WiFi sensor usingknown score values for similar places or time periods, the computationamount after database compilation is reduced and power consumption canbe suppressed.

Furthermore, in the case the device selection scores S(gps) and S(wifi)are below a predetermined threshold value, the GPS sensor and the WiFisensor may both be controlled so as not to operate for a predeterminedperiod of time. When considering the movement speed at the time of auser taking an action, in the case the device selection scores are belowthe predetermined threshold value, the scores are assumed to remain lowfor a while. Thus, while the scores are low, there is virtually noinfluence on position detection even if the GPS sensor and the WiFisensors do not operate. By not causing the GPS sensor and the WiFisensor to operate for a predetermined period of time, power consumptioncan be reduced.

Next, an operation of the information processing apparatus 100 at thetime of performing the acquisition times control process according tothe second embodiment will be described with reference to FIG. 13. FIG.13 is a flow chart showing an operation of the information processingapparatus 100 at the time of performing the acquisition times controlprocess according to the second embodiment.

First, the acquisition times control unit 240 calculates the deviceselection scores of a plurality of position sensors (step S202). Thatis, the acquisition times control unit 240 calculates the deviceselection score S(gps) of a GPS sensor and the device selection scoreS(wifi) of a WiFi sensor.

Next, the acquisition times control unit 240 determines whether deviceselection scores calculated in the past are registered in a database(step S204). In the case the device selection scores are determined instep S204 as not registered (No), the acquisition times control unit 240registers the calculated device selection scores S(gps) and S(wifi) inthe database (step S206).

Next, the acquisition times control unit 240 determines whether both thedevice selection scores S(gps) and S(wifi) are below a threshold value(step S208). In the case both the device selection scores S(gps) andS(wifi) are below the threshold value in step S208 (Yes), theacquisition times control unit 240 does not cause either of the GPSsensor and the WiFi sensor to operate (step S210).

In the case one of the device selection scores S(gps) and S(wifi) isabove the threshold value in step S208 (No), the acquisition timescontrol unit 240 determines which of the device selection scores S(gps)and S(wifi) is above the threshold value (step S212).

In the case it is determined in step S212 that the device selectionscore S(gps) of the GPS sensor is above the threshold value (Yes), theacquisition times control unit 240 causes the GPS sensor, of the GPSsensor and the WiFi sensor, to operate (step S214). Then, the GPS sensordetects position information.

In the case it is determined in step S212 that the device selectionscore S(wifi) of the WiFi sensor is above the threshold value (No), theacquisition times control unit 240 causes the WiFi sensor, of the GPSsensor and the WiFi sensor, to operate (step S216). Then, the WiFisensor detects position information.

According to the second embodiment, in the case the informationprocessing apparatus 100 includes a plurality of position sensors, it ispossible to evaluate the characteristics or performance (detectionperformance) of the position sensors, and to select the most appropriateposition sensor from the plurality of position sensors and cause thesame to operate. With the most appropriate position sensor selected asdescribed above, power consumption can be suppressed.

3. Third Embodiment

An information processing apparatus 100 according to a third embodimenthas a function of predicting the movement of a user based on the mostrecent or past path along which the user has moved. In the case it ispossible to accurately predict the movement of the user, the informationprocessing apparatus 100 does not perform acquisition of position data.It is thereby needless to cause the position information detection unit140 to operate, and power consumption can be suppressed.

An acquisition times control process with respect to positioninformation according to the third embodiment will be described withreference to FIG. 14. FIG. 14 is a schematic diagram for describing anoverview of an acquisition times control process with respect toposition information according to the third embodiment.

The acquisition times control unit 240 refers to the record of the mostrecent or past position data of a user, and predicts (or complements)the current position data using a probability model such as a hiddenMarkov model (HMM). Then, as shown in FIG. 14, in the case the movementof the user can be predicted, the acquisition times control unit 240does not cause a position sensor to operate, and in the case themovement of the user is difficult to predict, the acquisition timescontrol unit 240 causes the position information detection unit 140 tooperate. For example, when assuming that a predicted existenceprobability of the user is P, the position information detection unit140 is caused not to operate for a predetermined period of time in thecase the existence probability P is above a threshold value.

Next, an operation of the information processing apparatus 100 at thetime of performing the acquisition times control process according tothe third embodiment will be described with reference to FIG. 15. FIG.15 is a flow chart showing an operation of the information processingapparatus 100 at the time of performing the acquisition times controlprocess according to the third embodiment.

First, the acquisition times control unit 240 predicts the currentposition of a user (step S302). For example, the acquisition timescontrol unit 240 predicts the current position by referring to therecord of the most recent or past position information of the user.

Next, the acquisition times control unit 240 determines, using aprobability model or the like, whether the probability of the predictedcurrent position being the correct position is equal to or greater thana threshold value (step S304). In the case the probability is equal toor greater than the threshold value in step S304 (Yes), the acquisitiontimes control unit 240 suspends the operation of the positioninformation detection unit 140 for a predetermined period of time (stepS306). Position detection by the position information detection unit 140is thereby temporarily suspended, and power consumption can besuppressed.

In the case the probability is below the threshold value in step S304(No), the acquisition times control unit 240 does not suspend theoperation of the position information detection unit 140, and performsaddition to the position record (step S310). Then, the acquisition timescontrol unit 240 repeats the processes described above (steps S302 toS310) until the present process is complete (step S312: No).

According to the third embodiment, in a case the current positioninformation can be predicted from position information detected in thepast, the current position information can be acquired from theprediction result while suppressing power consumption by suspending theoperation of the position information detection unit 140.

4. Fourth Embodiment

As described above, the information processing apparatus 100 canrecognize an action of a user by the action recognition processing unit230. An information processing apparatus 100 according to a fourthembodiment suppresses power consumption by controlling the number ofacquisition times with respect to position detection according to theresult of the action recognition process.

An acquisition times control process with respect to positioninformation according to the fourth embodiment will be described withreference to FIG. 16. FIG. 16 is a schematic diagram for describing anoverview of an acquisition times control process with respect toposition information according to the fourth embodiment.

The position of a user changes by the action of the user. Thus, theinterval of position detection can be adjusted according to a recognizedaction of the user. From this standpoint, the acquisition times controlunit 240 controls (adjusts) the number of acquisition times with respectto position detection according to the type of action recognized by theaction recognition processing unit 230. That is, the acquisition timescontrol unit 240 controls the acquisition cycle.

For example, in the case it is recognized by the action recognitionprocessing unit 230 that the user is shopping, the acquisition timescontrol unit 240 performs control so as to reduce the number of positiondetection times. This is because, as shown in FIG. 16, while the user isshopping, the user tends to move around a specific location, and themovement of the user is unlikely to be missed even if the number ofposition detection times is reduced.

In the case it is recognized by the action recognition processing unit230 that the user is doing housework or working, the acquisition timescontrol unit 240 performs control so as to further reduce the number ofposition detection times than for shopping. This is because localizedmovement is expected in relation to housework and work, and the movementof the user is unlikely to be missed in the case of localized movementeven if the number of position detection times is actively reduced.

In the case it is recognized by the action recognition processing unit230 that the user is on a train, the acquisition times control unit 240performs control so as to reduce the number of position detection times.This is because, since trains typically move linearly alongpredetermined tracks, the movement of the user is unlikely to be missedeven if the number of position detection times is reduced. Additionally,similar control is possible for vehicles other than the trains as longas they move linearly.

In the case it is recognized by the action recognition processing unit230 that the user is in a still state, the acquisition times controlunit 240 performs control so as to further reduce the number of positiondetection times than for the actions described above, because the useris less likely to move.

In the case movement of the user of changing direction is not detectedby the action recognition processing unit 230, the acquisition timescontrol unit 240 performs control so as to reduce the number of positiondetection times. This is because, if the movement of changing directiondoes not happen often during movement, such as walking or running, ofthe user, the movement of the user is unlikely to be missed even if thenumber of position detection times is reduced.

In the above, the acquisition times control unit 240 is to control thenumber of acquisition times according to the type of action, but,without being limited to the above, the number of acquisition times mayalso be controlled according to the degree of one action, for example.For example, the acquisition times control unit 240 performs control soas to reduce the number of position detection times, in the case walkingspeed is slow or the increase rate of the number of steps is low. Since,in the case the walking speed is slow or the increase rate of the numberof steps is low, the position is not greatly changed within a shortperiod of time, reducing the number of position detection times will notcause the movement of the user to be likely to be missed, while itenables to suppress power consumption.

Next, an operation of the information processing apparatus 100 at thetime of performing the acquisition times control process according tothe fourth embodiment will be described with reference to FIG. 17. FIG.17 is a flow chart showing an operation of the information processingapparatus 100 at the time of performing the acquisition times controlprocess according to the fourth embodiment.

First, the action recognition processing unit 230 performs actionrecognition with respect to a user (step S402). Then, the acquisitiontimes control unit 240 decides the amount of adjustment of the number ofacquisition times with respect to position detection, according to thetype of action recognized by the action recognition processing unit 230(steps S404 to S418).

Specifically, in the case it is recognized that the user is shopping(step S404: Yes), the acquisition times control unit 240 decides anappropriate amount of adjustment A1 (the amount by which the number ofposition detection times is reduced) that is in accordance with theaction (shopping) (step S406).

In the case it is recognized that the user is working (step S408: Yes),the acquisition times control unit 240 decides an appropriate amount ofadjustment A2 (the amount by which the number of position detectiontimes is reduced) that is in accordance with the action (working) (stepS410).

In the case it is recognized that the user is on a train (step S412:Yes), the acquisition times control unit 240 decides an appropriateamount of adjustment A3 (the amount by which the number of positiondetection times is reduced) that is in accordance with the action (on atrain) (step S414).

In the case it is recognized that the user is in a still state (stepS416: Yes), the acquisition times control unit 240 decides anappropriate amount of adjustment A4 (the amount by which the number ofposition detection times is reduced) that is in accordance with theaction (still state) (step S418).

Next, the acquisition times control unit 240 adjusts the number ofacquisition times with respect to position detection according to theamount of adjustment A1, A2, A3, or A4 which has been decided (stepS420). For example, the acquisition times control unit 240 performscontrol, depending on the action, so as to reduce the number ofacquisition times with respect to position detection. Then, the positioninformation detection unit 140 detects the position information of theuser by the adjusted number of acquisition times.

According to the fourth embodiment, by controlling the number ofacquisition times with respect to position detection according to thetype of action recognized, for example, by reducing the number ofacquisition times depending on the type of action, power consumption atthe time of position detection can be suppressed.

5. Fifth Embodiment

An information processing apparatus 100 according to a fifth embodimentpredicts a continuation time of a recognized action, and suspends thefollowing action recognition process for the predicted continuationtime. Then, the information processing apparatus 100 suspends theoperation of both the position sensor and the motion sensor while theaction recognition process is being suspended to thereby suppress powerconsumption.

An acquisition times control process with respect to positioninformation according to the fifth embodiment will be described withreference to FIG. 18. FIG. 18 is a schematic diagram for describing anoverview of an acquisition times control process with respect toposition information according to the fifth embodiment.

Considering an actual action of a user, when one action is recognized,this one action tends to continue for over a specific period of time.During this continuation time, the position or the like can be assumedto change only within a specific range, and, thus, inconvenience ishardly caused even if the action recognition process is suspended. Fromsuch a standpoint, the acquisition times control unit 240 predicts thecontinuation time according to the type of action recognized, andsuspends the action recognition process during the predictedcontinuation time.

For example, in the case it is recognized by the action recognitionprocessing unit 230 that the user is on a train, the acquisition timescontrol unit 240 predicts that the state of being on a train willcontinue for some time, and suspends the next action recognition processfor several minutes (time t2 and t3 in FIG. 18), for example. Duringsuspension of the action recognition process, the acquisition timescontrol unit 240 suspends the operation of both the position informationdetection unit 140 and the motion sensor 142.

In the case it is recognized by the action recognition processing unit230 that the user is moving on foot, the acquisition times control unit240 predicts that the state of moving on foot continues for a certainperiod of time, although short, and suspends the next action recognitionprocess for several tens of seconds, for example. During suspension ofthe action recognition process, the acquisition times control unit 240suspends the operation of both the position information detection unit140 and the motion sensor 142.

Next, an operation of the information processing apparatus 100 at thetime of performing the acquisition times control process according tothe fifth embodiment will be described with reference to FIG. 19. FIG.19 is a flow chart showing an operation of the information processingapparatus 100 at the time of performing the acquisition times controlprocess according to the fifth embodiment.

First, the action recognition processing unit 230 performs actionrecognition with respect to a user (step S502). Then, the acquisitiontimes control unit 240 decides the suspension time for the actionrecognition process according to the type of action acquired (steps S504to S510).

Specifically, in the case it is recognized that the user is on a train(step S504: Yes), the acquisition times control unit 240 decides anappropriate suspension time T1 that is in accordance with the action (ona train) (step S506).

In the case it is recognized that the user is moving on foot (step S508:Yes), the acquisition times control unit 240 decides an appropriatesuspension time T2 that is in accordance with the action (moving onfoot) (step S510).

Next, the acquisition times control unit 240 suspends, during the actionof the user, the action recognition process for the suspension time T1or T2 which has been decided (step S512). During suspension of theaction recognition process, the operation of both the positioninformation detection unit 140 and the motion sensor 142 is alsosuspended. Additionally, it is also possible to have the operation ofone of the position information detection unit 140 or the motion sensor142 suspended.

According to the fifth embodiment, by predicting the continuation timeof an action of a user for whom action recognition has been performedand suspending the operation of the position information detection unit140 for the predicted continuation time, power consumption can besuppressed.

Additionally, heretofore, different processes have been described forthe first to fifth embodiments, but it is also possible to combine theprocesses of a plurality of embodiments. Furthermore, the process ofeach embodiment may be performed together.

It should be understood by those skilled in the art that variousmodifications, combinations, sub-combinations and alterations may occurdepending on design requirements and other factors insofar as they arewithin the scope of the appended claims or the equivalents thereof.

Additionally, the steps described in the flow charts of the embodimentsabove include, of course, processes performed chronologically accordingto the order described, and also processes that are performed inparallel or individually without being performed chronologically. Also,it is needless to say that the order may be changed as appropriate forsteps that are chronologically processed.

Additionally, the following configurations are also within the technicalscope of the present disclosure.

(1) An information processing apparatus including:

a position sensor for detecting position information: and

a detection times control unit for acquiring detection accuracyinformation regarding detection accuracy of the position sensor based ona detection result of the position sensor, and controlling the number ofdetection times of the position sensor based on the acquired detectionaccuracy information.

(2) The information processing apparatus according to (1), wherein thedetection times control unit divides the detection accuracy, whosedegrees cover a predetermined range, into each degree, and controls thenumber of detection times for each degree obtained by the division.(3) The information processing apparatus according to (2), wherein thedetection times control unit performs control so as to reduce stepwisethe number of detection times for a region for which the degree is highwithin the predetermined range.(4) The information processing apparatus according to (2) or (3),wherein the detection times control unit performs control so as toreduce stepwise the number of detection times for a region for which thedegree is low within the predetermined range.(5) The information processing apparatus according to any of (2) to (4),wherein, in a case the predetermined range is divided into a smallregion, a medium region, and a large region according to a level of thedegree, the detection times control unit controls the number ofdetection times for the medium region to be greater than the number ofdetection times for the small region and the large region.(6) The information processing apparatus according to any of (1) to (5),further including:

a first position sensor and a second position sensor, each as theposition sensor,

wherein the detection times control unit selects, and causes to operate,one of the first position sensor or the second position sensor, based onthe acquired detection accuracy information.

(7) The information processing apparatus according to (6), wherein thedetection times control unit quantifies detection performance of thefirst position sensor and detection performance of the second positionsensor, and selects, and causes to operate, one position sensor with agreater value.(8) The information processing apparatus according to (6) or (7),wherein, in a case values of the detection performance of the firstposition sensor and the second position sensor are below a thresholdvalue, the detection times control unit suspends the first positionsensor and the second position sensor for a predetermined period oftime.(9) The information processing apparatus according to any of (1) to (8),wherein, in a case current position information can be predicted fromthe position information detected in past, the detection times controlunit suspends the position sensor.(10) The information processing apparatus according to any of (1) to(9), further including:

an action recognition unit for recognizing an action of a user,

wherein the detection times control unit controls the number ofdetection times based on a recognition result of the action recognitionunit.

(11) The information processing apparatus according to (10), wherein thedetection times control unit controls the number of detection timesaccording to a type of the action of the user recognized by the actionrecognition unit.

(12) The information processing apparatus according to (10), wherein thedetection times control unit predicts a continuation time of one actionof the user recognized by the action recognition unit, and suspends theposition sensor during the predicted continuation time.(13) An information processing method including:

acquiring, based on a detection result of a position sensor fordetecting position information, detection accuracy information regardingdetection accuracy of the position sensor; and

controlling, based on the acquired detection accuracy information, thenumber of detection times of the position sensor.

(14) A program for causing a computer to execute:

acquiring, based on a detection result of a position sensor fordetecting position information, detection accuracy information regardingdetection accuracy of the position sensor; and

controlling, based on the acquired detection accuracy information, thenumber of detection times of the position sensor.

The present application contains subject matter related to thatdisclosed in Japanese Priority Patent Application JP 2011-177850 filedin the Japan Patent Office on Aug. 16, 2011, the entire content of whichis hereby incorporated by reference.

What is claimed is:
 1. An information processing apparatus comprising: aposition sensor for detecting position information; and a detectiontimes control unit for acquiring detection accuracy informationregarding detection accuracy of the position sensor based on a detectionresult of the position sensor, and controlling the number of detectiontimes of the position sensor based on the acquired detection accuracyinformation, wherein the detection accuracy information indicateslikelihood of an accurately detected position by the position sensorcorresponding to respective detection results of the position sensor,and the detection times control unit sets a particular value for thenumber of detection times for each degree of a plurality of degrees ofthe likelihood indicated by the detection accuracy information, whereinthe detection times control unit sets the particular value of the numberof detection times for each degree to reduce a power consumption of theposition sensor.
 2. The information processing apparatus according toclaim 1, wherein the detection times control unit divides the detectionaccuracy, whose degrees cover a predetermined range, into each degree,and controls the number of detection times for each degree obtained bythe division.
 3. The information processing apparatus according to claim2, wherein the detection times control unit performs control so as toreduce stepwise the number of detection times for a region for which thedegree is high within the predetermined range.
 4. The informationprocessing apparatus according to claim 2, wherein the detection timescontrol unit performs control so as to reduce stepwise the number ofdetection times for a region for which the degree is low within thepredetermined range.
 5. The information processing apparatus accordingto claim 2, wherein, in a case the predetermined range is divided into asmall region, a medium region, and a large region according to a levelof the degree, the detection times control unit controls the number ofdetection times for the medium region to be greater than the number ofdetection times for the small region and the large region.
 6. Theinformation processing apparatus according to claim 1, furthercomprising: a first position sensor and a second position sensor, eachas the position sensor, wherein the detection times control unitselects, and causes to operate, one of the first position sensor or thesecond position sensor, based on the acquired detection accuracyinformation.
 7. The information processing apparatus according to claim6, wherein the detection times control unit quantifies detectionperformance of the first position sensor and detection performance ofthe second position sensor, and selects, and causes to operate, oneposition sensor with a greater value.
 8. The information processingapparatus according to claim 6, wherein, in a case values of thedetection performance of the first position sensor and the secondposition sensor are below a threshold value, the detection times controlunit suspends the first position sensor and the second position sensorfor a predetermined period of time.
 9. The information processingapparatus according to claim 1, wherein, in a case current positioninformation can be predicted from the position information detected inpast, the detection times control unit suspends the position sensor. 10.The information processing apparatus according to claim 1, furthercomprising: an action recognition unit for recognizing an action of auser, wherein the detection times control unit controls the number ofdetection times based on a recognition result of the action recognitionunit.
 11. The information processing apparatus according to claim 10,wherein the detection times control unit controls the number ofdetection times according to a type of the action of the user recognizedby the action recognition unit.
 12. The information processing apparatusaccording to claim 10, wherein the detection times control unit predictsa continuation time of one action of the user recognized by the actionrecognition unit, and suspends the position sensor during the predictedcontinuation time.
 13. An information processing method comprising:acquiring, based on a detection result of a position sensor fordetecting position information, detection accuracy information regardingdetection accuracy of the position sensor; and controlling, based on theacquired detection accuracy information, the number of detection timesof the position sensor, wherein the detection accuracy informationindicates likelihood of an accurately detected position by the positionsensor corresponding to respective detection results of the positionsensor, and a particular value for the number of detection times is setfor each degree of a plurality of degrees of the likelihood indicated bythe detection accuracy information, and wherein the particular value ofthe number of detection times for each degree is set so as to reduce apower consumption of the position sensor.
 14. A non-transitorycomputer-readable medium having embodied thereon a program, which whenexecuted by a computer causes the computer to execute a method, themethod comprising: acquiring, based on a detection result of a positionsensor for detecting position information, detection accuracyinformation regarding detection accuracy of the position sensor; andcontrolling, based on the acquired detection accuracy information, thenumber of detection times of the position sensor, wherein the detectionaccuracy information indicates likelihood of an accurately detectedposition by the position sensor corresponding to respective detectionresults of the position sensor, and a particular value for the number ofdetection times is set for each degree of a plurality of degrees of thelikelihood indicated by the detection accuracy information, and whereinthe particular value of the number of detection times for each degree isset so as to reduce a power consumption of the position sensor.